In many different radio systems, it is necessary to synchronize a receiver to properly receive and process an incoming data stream. This is so, as a transmitter and receiver may suffer from variations in symbol timing and in carrier frequency generation and so forth. Furthermore, synchronization is needed to enable proper alignment in time and frequency of processing circuitry within a receiver. In typical receiver systems, synchronization is generally performed based on a priori knowledge of certain information received within an incoming data stream.
That is, many communications standards insert synchronization information periodically during a data stream so that a receiver can synchronize its processing according to this synchronization information. However, in certain communication systems such as a digital audio broadcasting (DAB) system, such synchronization information is communicated at a relatively slow rate, which can cause difficulties in synchronization, particularly in the presence of noise and multipath interference.